package com.hlbspringcloud.contentcenter.sentineltest;

import com.alibaba.csp.sentinel.adapter.servlet.callback.UrlBlockHandler;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import com.alibaba.csp.sentinel.slots.block.authority.AuthorityException;
import com.alibaba.csp.sentinel.slots.block.degrade.DegradeException;
import com.alibaba.csp.sentinel.slots.block.flow.FlowException;
import com.alibaba.csp.sentinel.slots.block.flow.param.ParamFlowException;
import com.alibaba.csp.sentinel.slots.system.SystemBlockException;
import com.fasterxml.jackson.databind.ObjectMapper;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;
import org.springframework.stereotype.Component;
import sun.nio.cs.ext.MS874;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.SyncFailedException;

/**
 * @Description:
 * @PROJECT_NAME: spring-cloud-alibaba
 * @CLASS_NAME:
 * @Author: huanglibin
 * @Date: 2020-06-03 23:41
 * @Version: 1.0
 */
@Component
public class MyUrlBlockHandler implements UrlBlockHandler {
    @Override
    public void blocked(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, BlockException e) throws IOException {
        ErrorMsg msg = null;
        if (e instanceof FlowException) {
            msg = ErrorMsg.builder()
                    .status(100)
                    .msg("限流了")
                    .build();
        } else if (e instanceof DegradeException) {
            msg = ErrorMsg.builder()
                    .status(101)
                    .msg("降级了")
                    .build();
        } else if (e instanceof ParamFlowException) {
            msg = ErrorMsg.builder()
                    .status(102)
                    .msg("热点参数限流")
                    .build();
        } else if (e instanceof SystemBlockException) {
            msg = ErrorMsg.builder()
                    .status(103)
                    .msg("系统规则(负载/...不满足要求)")
                    .build();
        }else if(e instanceof AuthorityException){
            msg = ErrorMsg.builder()
                    .status(104)
                    .msg("授权规则不通过")
                    .build();
        }
        //http状态码
        httpServletResponse.setStatus(500);
        httpServletResponse.setCharacterEncoding("utf-8");
        httpServletResponse.setHeader("Content-Type","application/json;charset=utf-8");
        httpServletResponse.setContentType("application/json;charset=utf-8");
        //springmvc自带的json操作工具,叫jackson(json对象转字符串，字符串转json对象)
        new ObjectMapper().writeValue(
                httpServletResponse.getWriter(), msg
        );
    }
}

@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
class ErrorMsg{
    private Integer status;
    private String msg;
}
